Julius schaeppi



(Nd Model.)

J. S OHAEPPI.

SAFETY CENTER PINION FOR WATCHES.

No. 286,851. Patented 001516, 1883.. I

UNITED STATES PATENT Orrrcs.

JULIUS SOHAEPPI, OF CINCINNATI, OHIO, ASSIGNOR OF T VO TIIIRDS TO EDXVARD S. AYNE AND JEROME B. HOLMAN, OF SAME PLACE.

SAFETY CENTER-PINION FOR \NATCHES.

SPECIFICATION forming part of Letters Patent No. 286,851, dated October 16, 1883.

Application filed January :20, 1883.

T0 aZZ 1072 0721, it may concern:

Be it knownthat I, J ULIUS Serranrrr, a citizen of the United States, and a resident of Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in \Vatehes, of which the following is a specification.

The present invention relates to that class of safety center-pinions for watches which are automatically released on the rupture of the mainsprin I-Ieretofore it has been proposed to effect the connection of the pinion with its arbor or the center-wheel by screw-threads, ratchetand-pawl devices, clutches, and other expedients. All these devices involve the use of a center-pinion of a peculiar formation in order to adapt it to engage with the stop device on the arbor or center-wheel, and consequently such pinions have not given entire satisfaction, as they add to the expense of the watch and require considerable skill in manui'acturing, iitting, and repairing them. It has also been proposed to obviate, the disadvantages of clutches requiring a special construction of pinion -by attaching a short arm by a pivot or spring hinge to the center-wheel or to its arbor, said arm having a face or projection at its free end which abuts against one of the teeth of the pinion, so as to lock the latter when the spring is intact, and permit it to turn backward when the spring breaks, the pinion in such an event, by reason of its backward movement, gliding or sweeping over the projection of the stop-arm and pushing it aside.

This construction does not require a pinion of, a special construction; but the stoparm needs to be elastic or yielding, so as to allow it to be depressed by the backward movement of the pinion, the latter being itself held between collars, so that it cannot have an endwise movement 011 its arbor. -My invention, on the con- I trary, only has reference to that class of pinions which have a slight movement on their arbors, so as to permit themto glide up and ride over a rigid stop set in the hub of the centerwheel and fitting between a pair of teeth of the pinion. Said stop is a simple pin having a flat vertical face and an inclined vertical face, the pin being of such a size and set so (No model.)

as to not interfere with the proper mesh of the pinion into its'appropriate wheel. \Vhen the pinion is in its normal position, the vertical or flat face thereof bears against one of the teeth and acts as a stop, and when the spring breaks the pinion jumps or moves on its arbor and glides over the inclined face of the stop-pin, so as to prevent further damage to the watch mechanism.

It will. be understood that the stop-pin can be easily applied in position, and that it occupies the space between a pair of teeth on the pinion, so as not to interfere with the free movement thereof.

I11 the accompanying drawings, Figure l is a plan view of an ordinary watch-movement, designed to show the application of my invention. Fig. 2 is a central sectional elevation, on an enlarged scale, of the center wheel and pinion of awatch-movement and their mounting-arbor illustrative of my invention. Fig. 3 is an enlarged broken sectional elevation of the center wheel and pinion, showing the construction and arrangement of the stop or pin between the teeth of the pinion on a line at right angles to that shown in Fig. 2.

A represents the customary pillar-plate of a watch, upon which the train of wheels and other mechanism composing the movement thereof are mounted.

13 represents the barrel containing the mainspring, and O the great wheel placed around it.

D is the center-wheel, which is driven by the action of wheel 0 upon its pinion E. The center-pinion E is mounted loosely or freeto revolve in one direction upon the arbor c, which is journaled in the usual manner.

a is a washer set upon the pinion E, to hold it in place and at the same time permit it to revolve freely upon its arbor.

F is a pin set into the hub of the center-- the pinion firmly against the stop F, to drive the movement. The inclined face f of the pin F permits the teeth of the pinion to ride over it on a reverse movement thereof, caused IOO by the recoil of the mainspring, suflicient space being provided between the top of the pinion and the plate fitting over it to permit the rise or Vertical play thereof. 4

vertical face, and with an inclined face fitted I 5 in its hub portion, with the arbor and the pinion adapted to be locked by said stop-pin and to glide up and over the same when moving 5 The remainder of the mechanism shown in in a backward direction, substantially as de- I the drawings is as customary, and it is not necscribed. 2o essary to describe it herein. In testimony whereof I have hereunto set my It is obvious that a center-pinion for a clock vhand in the presence of two subscribing witor other mechanism could be mounted in the nesses. 10 same manner as herein set forth and like bone 1 fioial results attained. JULIUS SOHAEPPI' I claim Witnesses:

The combination of the center-wheel havin g the rigid stop-pin provided with a straight J OHN A. Somrrnr, JNo. E. J ONES. 

